Angular reactive forms validation while typing

I´m working on this form and want to validate while typing. The current behavior it´s that I select the input, type and when I click on other site then the error it´s showing. I think the error it's happening when i set control, valid and dirty, but i can't figure it out.

Typescript

buildForm(): void {
this.userForm = this.fb.group({
'email': ['', [
Validators.required,
Validators.pattern('[a-z0-9._%+-]+@[a-z0-9.-]+\.[a-z]{2,3}$')
]
],
'password': ['', [
Validators.required,
Validators.minLength(6),
Validators.maxLength(25)
]
],
});
this.userForm.valueChanges.subscribe(data => this.onValueChanged(data));
}

onValueChanged(data?: any) {
if (!this.userForm) { return; }
const form = this.userForm;
for (const field in this.formErrors) {
// clear previous error message (if any)
this.formErrors[field] = '';
const control = form.get(field);
if (control && control.invalid && control.dirty) {
const messages = this.validationMessages[field];
for (const key in control.errors) {
this.formErrors[field] += messages[key] + ' ';
}
}
}
}


Function onValueChanged() change this object

formErrors = {
'email': '',
'password': ''
};


And this object has the validation messages.

validationMessages = {
'email': {
'required': 'Email is required',
'pattern': 'Email is invalid'
},
'password': {
'required': 'Password is required',
'minlength': 'Debe tener 6 caracteres como mínimo',
'maxlength': 'Password cannot be more than 40 characters long.',
}
};


HTML

<mat-form-field class="example-full-width">
<input matInput placeholder="Email" formControlName="email" required>
<mat-error *ngIf="formErrors.email" align="start" class="form__error">
{{ formErrors.email }}
</mat-error>
</mat-form-field>
<mat-form-field class="example-full-width">
<input matInput placeholder="Password" type="password" formControlName="password" required>
<mat-error *ngIf="formErrors.password" align="start" class="form__error">
{{ formErrors.password }}
</mat-error>
</mat-form-field>

Continue reading...